Clamping device



Nm., w, w35., C. M, RUTTER mm3 CLAMPING DEVICE Filed Aug. l0, 1952 Gttornegs atented Nov. 119, 1935 i nach UNTED STATES PATENT OFFICE CLMPENG DEVC Clyde M. Rutter, Massillon, Ohio, assigner t'o Republic Steel Corporation, Youngstown, Ohio, a corporation of New Jersey Application August '10, 1932, Serial No.4 V628,207

1 Claim.

This invention relates to the art of surfaci sheets by grinding. cifcally to a clamping device for securing t it relates more spernetai sheets to a recprocable table during the grinding operation.

employed which called for the piercing of t sheets, resulting in considerable scrap loss, not to mention the tendency on the part of the sheet to buckle during the grinding operation, resulting in a relatively high percentage of loss from this source. The sheets were also held by means of bolted clamps.

However, the adjustment and tightening of the clamps took considerable time and effort which did not lend itself to economical production. Ordinarily, the clamping devices were placed at the ends of the sheet and would often interfere with the grinding wheel the table were given a full stroke. Hence, t

if he end zone of each sheet remained unfinished and constituted so much scrap loss.

This invention comprehends a manually operable clamping device having a portion for e gaging the work and a lever for operating said portion. The portion which engages the work adapted to grip the sheet in that zone whi is ch travels back and forth beneath the grinding wheel. ing wheel, the upper surface of the part is arc To prevent interference with the grindately contoured and struck on a slightly greater radius than the grinding wheel which will allow the part to travel under the grinding wheel limited distance, determined by the clearance between the wheel and the sheet, which will allow a full stroke of the table without the clamping means and grinding wheel interfering.

One object of this invention is to provide manually operable devicefor clamping the end of a sheet to be ground that will permit the sheet to be readily and easily grasped and securely held during the grinding operation.

Another object of this invention is to overcome scrap loss at the ends of the sheets by permitting of a full stroke of the table.

Still another object of this invention is to provide a clamping means that will not interfere with the grinding wheel duri reciprocation of the table.

Referring now to the drawing and particularly 16 v Figure 1 therel is illustrated a grinding wheel A, a reciprocating table of a sheet grinding machine B and the clamping means C. lne table B is adapted to have secured thereto in any suitable manner a base plate l in which is formed 20 a laterally extending T-s1ot 2. The formed end of the base plate is preferably notched as at 3 to receive the end of a rider sheet t upon which is disposed a sheet of linoleum 5 or other fibrous material acting as a cushion for the metal sheet 25 during the grinding operation. Both the rider sheet and the covering of linoleum are secured to the base plates in the notched portion thereof through the medium of bolts E. Disposed en the upper surface of the linoleum is the metallic 30 sheet to be polished, one end thereof being securely clamped to the base plate by means of my novel clamp C.

The clamp C (Figure 2) comprises a rocker arm 1 mounted for pivotal movement about a 35 transverse axis, one end thereof having a serrated surface 8 adapted to contact with the end of the sheet and to compress the end thereof to the base plate of the table. The top surface of the rocker arm 'l in the zone ahead of the axis 40 is provided with an arcuate surface of complemental configuration with the surface of the grinding wheel thereby permitting the grinding Wheel to approach as near the end of the sheet `as is possible on one hand and to permit the 45 rocker arm to travel under the grinding wheel a maximum distance. The radius of the arcuate face of the rocker arm 'l depends in the main on the radius of the grinding wheel. For instance, the radius R struck from the center of the grind- 50 ing wheel may be slightly less than the radius R2 which designates the radius of the top surface of the rocker arm. It will be appreciated that this method ofv determining the radius will give the rocker arm a maximum stroke Without inter- 55 as to be adaptable to sheets of varying widths.

The opposite end of the lever arm l is preferably bifurcated as at I i to receive a cam element i2 which hasa handle i3 that may be readily grasped by the operator. When the block is engaging the T-slot ofthe base member the surface of the cam member I2 is adapted to coi-act with the surface of the base plate so thatrany movement of the handle i3 will raise or lower the end or" the rocker arm 'I thereby clamping a sheet in position or releasing the sheet from the table. Y

VAlthouglfi I have shown the rocker arm with an arcuate upper side, it will be appreciated that Y the arm may be wedge shaped in this zone or may take any one of a number of shapes that will give the desiredresult, namely that of grasping the sheet in such a manner that a full stroke of the table will be permitted without interfer- Ving with the grinding Wheel.

Although the foregoing descriptionris necessarily of a detailed character in order to set forthk this invention itis to be understood that the specic terminology is not intended. to be restrictive or Conning and it is further understood that Various rearrangements of parts and modications of structural detail may be resortedrto without departing from the scope or spirit of this invention as herein claimed.

We claim:

In apparatus for grinding metal sheets and the 10VV like, the combination of a grinding wheel, a

reciprocating table for presenting a metal sheet to the grinding wheel, said .table being provided with a notched portion along one edge to receive the edge of a sheet to be ground and a slot exnotched portion of the table and a hand actuated cam element secured thereto remote from.k said nose portion, said camelement, when actuated,

operating to raise the end of the lever arm and 25 Y bring the nose portion into clamping relation with said table and frictionally lock the bearing block against movement within the slot.

CLYDE M. RU'I'I'ER. 

